1. Field of the Invention
The present invention relates to a portable terminal. More particularly, the present invention relates to a dormancy mode control method and apparatus for reducing electric current consumption of the portable terminal by minimizing the dormancy mode entry delay of the display in a power-off state.
2. Description of the Related Art
With the advance of information processing and semiconductor technologies, portable terminals are becoming powerful devices and widespread in use. Recent portable terminals (e.g. mobile phones) include many functions such as a voice call function, a music player function, a text messaging function, a digital broadcast receiver function, a short range radio communication function, and an internet access function. Typically, the portable terminals are powered by battery. For the battery-powered portable terminals, power saving is one of the significant issues. Particularly, since the recent portable devices, such as a smartphone, that are equipped with multiple processors (e.g. a Communication Processor (CP) and an Application processor (AP)) tend to consume more electric current, the power-saving issue is becoming more and more important.
Typically, the portable terminal, such as a smartphone, equipped with multiple processors is configured such that the application processor does not receive unnecessary events from the communication processor in the display power-off state. Accordingly, in the conventional portable terminal, the application processor does not receive any communication channel connection release message from the communication processor or, if received, ignores the message without any action. In this case, the conventional portable terminal may fail immediate entry to the sleep mode after the connection release. In order to overcome this problem, the conventional portable terminal is configured to start a dormancy mode timer upon detection of the stop of data transmission of the communication processor in the display power-off state and, when the dormancy mode timer expires, the application processor enters the dormancy mode.
If the dormancy mode timer is initiated, the application processor calls a wake-lock function to prevent the application processor from entering the dormancy mode until the dormancy mode timer expires. Accordingly, the portable terminal may not enter the dormancy mode even in a state fulfilling the dormancy mode entry condition. Particularly, when the dormancy mode timer is set to a relatively large value, the dormancy mode entry is further delayed, resulting in an increase of electric current consumption. That is, the conventional portable terminal has a drawback in that the application processor stays in a wake-state unnecessarily in the display power-off, which wastes electric current.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present invention.